Workshops for Defining the Complex Patient: Summary Some researchers have used the term complex patient to describe the demands placed on the health-care community by a certain proportion of the growing elderly population. Although intuitively useful, the concept of a complex patient has resisted concrete and well accepted conceptualization. Lack of operationalization has in turn slowed development of patient-centered management regimes designed to assist the complex patient. To address this issue, we propose a series of multidisciplinary workshops over a two year period involving behavioral and social scientists, health-care professionals, payers, and patients and their families that will seek to identify the various components of what constitutes a measurement tool for reliably and validly identifying complex patients. With proper operationalization, we argue that it will become easier to identify and manage elderly patients who might not otherwise receive appropriate care in an otherwise disjointed system of healthcare provision.